Vaillant VCW GB 242 EH Boiler - Is it Diverter Valve?

[trelo]

Just replaced DHW heat exchanger thinking my old problem is back! The hot water basicly was getting cooler and cooler. Usually in the past this meant DHW heat ex. was getting debris in it. So instead of cleaning the old one my thinking was to buy a second one and keep a clean one on stand-by when it got clogged. But no... not that this time...so i turned to the diverter valve and although it seems to be moving out and returning normally when i feel the flow into the DHW heat ex. it doesnt feel hot enough...the return out of the DHW ex. is cool so my suspicion is that something is a miss inside the diverter valve? the other thing i noticed is that when i switch back to C-Heating the flow pipe to DHW ex is getting hot but still cool on the return pipe? more suspicion is falling on the diverter valve... anyone can shed light on this.... many thanks

 

[bazdaman]

to check a faulty diverter, make sure the heating has not been on for a while and run the hot tap whilst feeling CH flow pipe, if it gets hot on CH flow pipe then diverter is passing and will need replacing.
hope this helps

 

[trelo]

to check a faulty diverter, make sure the heating has not been on for a while and run the hot tap whilst feeling CH flow pipe, if it gets hot on CH flow pipe then diverter is passing and will need replacing.
hope this helps

The Diverter was replaced 6 years ago... could it be that in needs cleaning maybe?

 

[bazdaman]

it sounds like you have had your problems due to muck in the heating system and should get that looked at as it will keep causing problems, if it is down to system being dirty then 6years is not bad going,
i personally would not try to clean diverter as it could cause all sorts of probs when it goes back in.

 

[trelo]

it sounds like you have had your problems due to muck in the heating system and should get that looked at as it will keep causing problems, if it is down to system being dirty then 6years is not bad going,
i personally would not try to clean diverter as it could cause all sorts of probs when it goes back in.

I did have a powerflush about 3 years ago.... saying that i have drained the system a few times due to fitting new rads... i know several drian downs can cause build up of muck again... are you saying just replace the diverter valve and not bother with cleaning or replacing bits inside then?

 

[Andygasman]

to check a faulty diverter, make sure the heating has not been on for a while and run the hot tap whilst feeling CH flow pipe, if it gets hot on CH flow pipe then diverter is passing and will need replacing.
hope this helps

As above, run the hot water from cold (rads cold too) and see if any heat passes down the heating flow pipe. Check this first before doing anything drastic. Then probs check flow rate and gas pressure etc.... Personally i'm i big fan of this boiler, it very reliable!

 

[Agile]

Assuming you had a NEW diverter valve then six years is a typical life for the diaphragm.

Commercially I would always replace the whole valve on this model.

Tony

 

[combispecialist]

wont be diverter mate on these.the diaphragm in these is activated by central heating water and not mains water,if it was changed years ago then it will definately not be it,it is very rarely a diverter fault.could a blockage in the weep tubes from the servo valve.if the diverter moves fully out on hw demand and fully in on central heating then both diverter and servo are doing their job,it would have to be sumthing else

 

[Gasguru]

Gas rate it and post back result...see FAQs

 

[Andygasman2010]

Gas rate it and post back result...see FAQs

assuming the diverter isn't passing to the rads (and i agree with 'combispecialist' that it's very rarely a diverter fault) check burner pressure/gas rate when on hot water. Basic checks first really then come back

 

[Agile]

Gas rate it and post back result...see FAQs

assuming the diverter isn't passing to the rads (and i agree with 'combispecialist' that it's very rarely a diverter fault) check burner pressure/gas rate when on hot water. Basic checks first really then come back

How do you expect a DIYer to measure burner pressures safely?

I dont think thats appropriate advice!

Tony

 

[Andygasman2010]

Gas rate it and post back result...see FAQs

assuming the diverter isn't passing to the rads (and i agree with 'combispecialist' that it's very rarely a diverter fault) check burner pressure/gas rate when on hot water. Basic checks first really then come back

How do you expect a DIYer to measure burner pressures safely?

I dont think thats appropriate advice!

Tony

fair comment! Duely noted

as it happens, i've tried to register for the CC but i've not had a reply. it still asked for corgi details as opposed to Gas Safe if that makes a difference... Does it usually take a while for registration

 

[albyadams44]

can some one give me some advice my heating is piping hot but i cannot get any hot water when heating is on i get hot water but on morning water is cold to luke warm

 

[Andygasman2010]

start your own thread and you'll get more responses, also give plenty of boiler detail i.e. make model or system type if applicable

 

[Agile]

You need to give your name, address, G-S reg nuber AND your photocard licence number.

It does seem to be taking ages at the moment. Unfortunately only the site owner does this and he is very busy but does not seem to want to delegate the job.

Tony